linux/net/netfilter/xt_mark.c
Jan Engelhardt f7108a20de netfilter: xtables: move extension arguments into compound structure (1/6)
The function signatures for Xtables extensions have grown over time.
It involves a lot of typing/replication, and also a bit of stack space
even if they are not used. Realize an NFWS2008 idea and pack them into
structs. The skb remains outside of the struct so gcc can continue to
apply its optimizations.

This patch does this for match extensions' match functions.

A few ambiguities have also been addressed. The "offset" parameter for
example has been renamed to "fragoff" (there are so many different
offsets already) and "protoff" to "thoff" (there is more than just one
protocol here, so clarify).

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-10-08 11:35:18 +02:00

123 lines
3 KiB
C

/*
* xt_mark - Netfilter module to match NFMARK value
*
* (C) 1999-2001 Marc Boucher <marc@mbsi.ca>
* Copyright © CC Computer Consultants GmbH, 2007 - 2008
* Jan Engelhardt <jengelh@computergmbh.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/netfilter/xt_mark.h>
#include <linux/netfilter/x_tables.h>
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Marc Boucher <marc@mbsi.ca>");
MODULE_DESCRIPTION("Xtables: packet mark match");
MODULE_ALIAS("ipt_mark");
MODULE_ALIAS("ip6t_mark");
static bool
mark_mt_v0(const struct sk_buff *skb, const struct xt_match_param *par)
{
const struct xt_mark_info *info = par->matchinfo;
return ((skb->mark & info->mask) == info->mark) ^ info->invert;
}
static bool
mark_mt(const struct sk_buff *skb, const struct xt_match_param *par)
{
const struct xt_mark_mtinfo1 *info = par->matchinfo;
return ((skb->mark & info->mask) == info->mark) ^ info->invert;
}
static bool
mark_mt_check_v0(const char *tablename, const void *entry,
const struct xt_match *match, void *matchinfo,
unsigned int hook_mask)
{
const struct xt_mark_info *minfo = matchinfo;
if (minfo->mark > 0xffffffff || minfo->mask > 0xffffffff) {
printk(KERN_WARNING "mark: only supports 32bit mark\n");
return false;
}
return true;
}
#ifdef CONFIG_COMPAT
struct compat_xt_mark_info {
compat_ulong_t mark, mask;
u_int8_t invert;
u_int8_t __pad1;
u_int16_t __pad2;
};
static void mark_mt_compat_from_user_v0(void *dst, void *src)
{
const struct compat_xt_mark_info *cm = src;
struct xt_mark_info m = {
.mark = cm->mark,
.mask = cm->mask,
.invert = cm->invert,
};
memcpy(dst, &m, sizeof(m));
}
static int mark_mt_compat_to_user_v0(void __user *dst, void *src)
{
const struct xt_mark_info *m = src;
struct compat_xt_mark_info cm = {
.mark = m->mark,
.mask = m->mask,
.invert = m->invert,
};
return copy_to_user(dst, &cm, sizeof(cm)) ? -EFAULT : 0;
}
#endif /* CONFIG_COMPAT */
static struct xt_match mark_mt_reg[] __read_mostly = {
{
.name = "mark",
.revision = 0,
.family = NFPROTO_UNSPEC,
.checkentry = mark_mt_check_v0,
.match = mark_mt_v0,
.matchsize = sizeof(struct xt_mark_info),
#ifdef CONFIG_COMPAT
.compatsize = sizeof(struct compat_xt_mark_info),
.compat_from_user = mark_mt_compat_from_user_v0,
.compat_to_user = mark_mt_compat_to_user_v0,
#endif
.me = THIS_MODULE,
},
{
.name = "mark",
.revision = 1,
.family = NFPROTO_UNSPEC,
.match = mark_mt,
.matchsize = sizeof(struct xt_mark_mtinfo1),
.me = THIS_MODULE,
},
};
static int __init mark_mt_init(void)
{
return xt_register_matches(mark_mt_reg, ARRAY_SIZE(mark_mt_reg));
}
static void __exit mark_mt_exit(void)
{
xt_unregister_matches(mark_mt_reg, ARRAY_SIZE(mark_mt_reg));
}
module_init(mark_mt_init);
module_exit(mark_mt_exit);